Functional Photoactive Materials

Multifunctional organic-inorganic hybrid materials

Organic-inorganic hybrids represent an elegant approach to manipulate the orientation and localisation of functional building blocks within a protective host material. Weak interactions (e.g. hydrogen bonding, ionic, pi-pi stacking) at the organic-inorganic interface (class I hybrids) can be harnessed to ensure homogenous mixing of the two components on the macroscale, whilst simultaneously promoting nanoscale phase separation and aggregation at the active interface. Alternatively, functional molecules can be covalently-grafted to the host material (class II) in order to control their placement and orientation. In addition, the host material itself may bring exploitable properties, which may yield hybrid materials with significantly superior properties due to a synergistic effect between individual components.

For example, we have recently shown that the immobilization of blue-emitting poly(fluorenes) within ureasil hybrids results in a dramatic enhancement of the photoluminescence quantum yield. Moreover, substitution with red- or orange-emitting conjugated polymers yields a solid-state white-light emitter with potential application in low energy indoor lighting.